When you’re trying to maintain a good oral hygiene routine, your toothbrush is bound to see a lot of action. Day in and day out, it gets used about twice a day, every day — morning and night, whether you’re feeling great or under the weather, in a hurry or not. And it's stored in the bathroom: a moist environment with the potential for exposure to plenty of bacteria (and not just the ones that live in your mouth). So after all of that service, does your toothbrush itself need any particular care or cleaning — and do you need to worry about getting sick from brushing?

Let’s answer the last question first. It’s very unlikely that you can re-infect yourself with an illness (a cold, for example) from using your own toothbrush. That’s because once you’ve been infected, the antibodies that are built up in response to the invading germs will generally prevent you from getting the same disease for some time afterward. Using someone else’s toothbrush, however, is a never a good idea — especially if they are sick (whether they show any symptoms or not), and doubly so if the bristles are still wet. It’s very possible to transfer all kinds of bacteria — even the bacteria that cause tooth decay — from person to person this way.

Can bacteria really survive for any length of time on your toothbrush? The short answer is yes, as they can (and do) live almost everywhere. But for people in a normal state of health, there’s no real reason to worry: Through long exposure, your body is generally quite capable of defending itself from these microorganisms. The American Dental Association states, “[T]here is insufficient clinical evidence to support that bacterial growth on toothbrushes will lead to specific adverse oral or systemic health effects.”

However, if you or a family member have a compromised immune system (due to radiation treatment, chemotherapy or disease, for example), it might make sense to take some precautions. Using an antibacterial mouthrinse before you brush can reduce the amount of bacteria in your mouth — and on your toothbrush. Washing the brush afterward with an antimicrobial cleaner or sanitizer can also decrease the level of bacteria that remains on the toothbrush.

For everyone else, it’s best to follow a few common-sense steps for toothbrush care: Rinse your brush with tap water after you use it, to remove any remaining toothpaste and debris; store it upright, where it can air-dry before it’s used again (not in a closed container, where bacteria can thrive); and get a new brush every three months. Your toothbrush is a major weapon in the fight against tooth decay — keeping it in good shape will help you maintain a healthy mouth and a healthy body.